docs(wandb): explain how to use W&B integration (#5607)
docs(wandb): explain how to use W&B integration (#5607)

* docs(wandb): explain how to use W&B integration

fix #5262

* Also mention TensorBoard

Co-authored-by: Julien Chaumond <a2e75dc0f7a441a5f83dcee1a3f7492a8c3d1d78@gmail.com>
huggingface/transformers,huggingface/transformers,huggingface/transformers,huggingface/transformers,huggingface/pytorch-transformers